Antimicrobial resistance and virulence genes inSalmonella entericaserovars isolated from droppings of layer chicken in two farms in Nigeria

Abstract

Aim This study aimed to investigate the isolation rate, antibiotic resistance and virulence genes of Salmonella enterica serovar from two commercial farms in Nigeria. Methods and Results Salmonella isolation was performed according to the United States Food and Drug Agency (USFDA) method. Serotyping, antimicrobial susceptibility testing, detection of resistance and virulence genes were done using the Kauffman–White Scheme, disc diffusion, minimum inhibitory concentration and real‐time polymerase chain reaction techniques. Salmonella serovars were isolated from only farm A at 22/50 (44.0%) while none were isolated from farm B. Salmonella Typhi, 9 (40.9%); Salmonella Typhimurium, 2 (9.1%), Salmonella Enteritidis, 2 (9.1%), Salmonella Pullorum, 1 (4.5%), Salmonella Kentucky, 4 (18.2%) were identified while 4 (18.2%) were untypable. Sixteen isolates (72.7%) showed multiple drug resistance and 17 different resistance profile types with AMP‐CHL‐TRM‐SXT as the most prevalent pattern. Resistance genes (blaTEM, 12/22 (54.5%) and virulence genes (InvA, sopB, mgtC and spi4D, 22/22 (100.0%), ssaQ, 16/22 (72.7%) and spvC, 13/22 (59.1%) were found, while blaSHV, blaCTX‐M, floR, tetA, tetB, tetG and LJSGI‐1 genes were absent. Conclusion Pathogenic Salmonella were isolated from the chicken droppings in this study. Most of these strains were resistant to antibiotics and possessed characteristics of virulence. Significance and Impact of the Study Chicken droppings from this study area contained pathogenic strains of Salmonella and a rare occurrence of Salmonella Typhi. The study revealed that the environment and the food chain could be at risk of contamination of highly virulent and antimicrobial‐resistant strains of Salmonella. These could affect the profitability of the poultry industry and food consumption. There is a need for caution in indiscriminate disposal of poultry waste and the use of uncomposted chicken droppings in soil amendment.

Occurrence of virulence factors and carbapenemase genes in Salmonella enterica serovar Enteritidis isolated from chicken meat and egg samples in Iraq

“…In their study, the most S. Enteritidis isolates (84.0%, n = 21/25) harbored tetA gene, whereas the tetB gene was only found in 2 isolates [ 18 ]. However, in another report by Shittu et al [ 27 ] from Nigeria, the tetA and tetB genes were not detected in any S. enterica serovars including S. Enteritidis isolates that was in contrast to our results. In another research by Siddiky et al [ 26 ] from Bangladesh, tetA and sul1 genes were detected in 3.44% of S. Enteritidis isolates that was lower than our study.…”

“…Also, Wang et al [31] from China reported higher incidence rates for sopB (100.0%) and spvC (93.8%) genes among Salmonella serovars isolated from 120 retail meat samples, including chicken (n = 45), duck (n = 30), and pork (n = 45). In the prior studies from Iran [6], Tunisia [23], and Nigeria [27], the prevalence rates of spvC gene were 50.8%, 45.8%, and 59.1%, respectively. In line with our results, Khodadadipour et al [32] from Iran detected the phoP/Q gene (33.3%) as the most prevalent virulence determinant in S. Enteritidis strains isolated from meat and egg samples.…”

Salmonella enterica Transmission and Antimicrobial Resistance Dynamics across One-Health Sector

“…These are essential for Salmonella to survive in the host environment and enter non-phagocytic cells. Animal waste commonly allows Salmonella to enter agricultural environments [76]. Plants and surface water used for irrigation or as a diluent for pesticides or fertilizers may be directly contaminated by animal feces [77].…”

“…Suppose the antibiotic resistances seen in human bacterial isolates are closely related to those seen in animal Salmonella enterica Transmission and Antimicrobial Resistance Dynamics across One-Health… DOI: http://dx.doi.org/10.5772/intechopen.109229 isolates. In that case, it may be possible to identify animal sources of resistant bacteria in human infections that can be targeted to reduce human disease [76,90,91]. This can be done by determining if the resistances seen in human bacterial isolates are similar to those seen in animal isolates [92].…”

“…Additionally, multidrug-resistant Salmonella strains were discovered in the aquatic habitat of some exotic pet animals, such as tortoises and turtles [100]. This might lead to an increased risk of zoonotic infections in people via direct contact with these animals [74,76,90].…”